I started my journey at the famed Gdansk Shipyard, home of Poland's solidarity movement in the 1980s. It was nearly midnight when I arrived and saw for the first time the Maersk McKinney Moller, the world's largest container ship.

I simply wasn't prepared for just how massive it is. The whole ship really can't be taken in, even standing at a distance, so I gave my neck a good stretch by scanning this behemoth end to end, and up and down.

That sense of scale was reinforced when I walked up the ship's steep gangway with Mikkel Linnet, a communications officer with Maersk. The ship's third officer, Siddhesh Naik, joked that most visitors ask where the elevator is because you need to climb two floors just to get to the main deck.

Everything about this ship is big.

Each link, or lug, in its anchor chain weighs about 500 pounds. It can carry more than 2 million bicycles or more than 100 million pairs of shoes.

It sits 240 feet high, roughly the same as a 20-story building. It's 1,300 feet long, or a quarter of a mile, and 200 feet wide. It can hold more than 18,000 of the standard 20-foot containers — about double what many other megaships can carry. If you put each container end to end, the line would stretch for about 70 miles.

And that's why we were already delayed by 12 hours. It was taking longer than expected for Polish longshoremen to finish loading and lashing down the thousands of containers carrying anything from electronic goods to furniture. Throughout the night I could hear the gigantic cranes hoist up containers — many weighing up to 25 tons — and stack them on this massive vessel.

The size of the Maersk McKinney Moller can also present challenges getting in and out of port. As we left Gdansk, the Danish captain, Jes Meinertz, sipped coffee and watched a Polish pilot deftly maneuver the ship around three nearby piers and into the open waters of the Baltic Sea.

The Maersk McKinney Moller was just launched last summer and is the first of a new class of megaships known as the Triple E. The vessel has that new car feel to it. Everything is clean and bright, and the crew is still familiarizing itself with all of the new bells and levers and whistles.

The ship was built to shuttle between Asia and northern Europe, the world's busiest trade route. No U.S. port can yet handle a ship this size. Several European ports improved their facilities, dredging their waterways and upgrading the size of their cranes in order to unload containers from this superwide vessel. Meinertz says the Chinese are constructing new terminals at an amazing rate.

"They are just building more and more terminals, bigger and bigger terminals. You have so much more gear available when you come alongside than in some of the European ports," he says.

It was in 2010 — during the global recession — that Maersk Lines made the decision to create this new class of megaship. Michael Heimann, senior portfolio manager at Maersk Line, was part of the development team. He says the challenge was coming up with a design that was at least 30 percent more efficient than other big container ships.

They needed to think "in different ways than what we had seen in ship design before," he says.

Heimann says Maersk made changes to the ship's engine size and its propellers, and it improved ways to capture energy to more efficiently power the vessel.

The ship moves 2 to 3 knots slower than others, which cuts both CO2 emissions and fuel costs — the ship's biggest expense — by at least half. Maersk also made fundamental changes to the shape of the vessel in order to get as many containers on board as possible. It's economy of scale, Heimann says.

"Obviously, the more containers that we can put on, the more containers that have to split the cost of the fuel on," he says.

Richard Meade with Lloyds List, a shipping industry news provider, says that's a great argument, but only if the ship is fully loaded.

"A ship like the Maersk McKinney Moller is a fantastic advance for the industry, as long as it is full. If it is half-empty, it is probably one of the most inefficient ships ever built," Meade says. "That is the great gamble."

It's a gamble Maersk is willing to make, based on the belief that global trade will bounce back from the recession. The company ordered 20 Triple E vessels from South Korean shipbuilder Daewoo at $185 million apiece. Half a dozen of the ships are already on the water. Other shipping companies have also placed orders for similar-sized vessels.

"We're very encouraged by the utilization, or the vessels being full," Schueler says. "In this year so far, I would say we are almost completely full."

On my second night on board, we headed into Danish waters. My jet lag prevented sleep, so I wandered around the ship. The massive containers stacked on deck were silhouetted by moonlight. I felt like a speck standing next to them.

I walked onto the bridge, where the glow of the instrument panels cut through the darkness. After a few moments, I could see a horizontal chain of lights just ahead. It was Denmark's Great Belt Bridge. I could feel myself duck as we went under it. There was only a 20-foot clearance between the top of the ship and the bottom of the bridge.

Within hours, we reached the port of Aarhus, Denmark, where I got off the ship. I walked down the long gangplank then onto the pier, taking one long last look at the Maersk McKinney Moller, a ship in a class of its own.

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RENEE MONTAGNE, HOST:

The global economy, of course, means that much, even most of what we see around us has arrived in the U.S. from another part of the world in container ships. Nowadays these ships are enormous, hauling thousands of containers carrying products that entertain us, transport us, clothe us, fill our offices and homes. And now there is a new class of ships - ships that dwarf all others.

NPR's Jackie Northam took a ride one on one.

JACKIE NORTHAM, BYLINE: I started my journey at the famed Gdansk shipyard - home of Poland's Solidarity movement in the 1980s. It was nearly midnight when I walked up the gangway of the Maersk McKinney Moller, the largest container ship in the world. Our departure was already delayed by 12 hours while Polish longshoremen finished loading and lashing down thousands of containers carrying anything from electronic goods to furniture.

(SOUNDBITE OF CRANES)

NORTHAM: Throughout the night you could hear the gigantic cranes hoist up containers - many weighing up to 25 tons - and stack them on this massive vessel.

Siddhesh Naik, the ship's third officer, says visitors are always surprised by the sheer size of the vessel.

SIDDHESH NAIK: The first thing everyone asks when they come here on this ship is where is the elevator, because you need to climb first two floors just to come to the main deck.

NORTHAM: Everything about this ship is big. It sits more than 20 stories high and is four football fields long. It can hold more than 18,000 20-foot containers - that's about double what many of the other mega-ships out there carry. Each link or lug in its anchor chain weighs about 500 pounds. It can carry more than two million bicycles, or more than 100 million pairs of shoes. And if you put each container on board end to end, the line would stretch for about 70 miles. It's a big ship.

(SOUNDBITE OF FOGHORN)

NORTHAM: But the size of the Maersk McKinney Moller can also present challenges, especially getting in and out of port. A Polish pilot, brought on board in Gdansk, has to slowly squeeze past three nearby piers.

UNIDENTIFIED MAN: (Foreign language spoken)

NORTHAM: I'm standing on the bridge of the Maersk McKinney Moller and we've just pushed off from the deepwater port in Gdansk. There's a lot of action here in the bridge as the pilot turns this enormous ship around. You can see three tugboats helping the ship as it moves. But it's an extremely tight fit. In front of me, there's a pier, to the left of the ship is a pier and to right of the ship is a pier. But it's a process that can be complicated by both wind and current.

CAPTAIN JES MEINERTZ: (Foreign language spoken)

NORTHAM: The Danish captain sips a cup of coffee as he watches the pilot deftly navigates the ship into the open waters of the Baltic Sea. Both men were trained on simulators how to handle this particular vessel. The Maersk McKinney Moller was only launched last summer. It's the first of a new class of megaships, known as the Triple E. The vessel has that new car feel to it - everything is bright and clean. And the crew is still familiarizing itself with all the new bells and levers and whistles.

MEINERTZ: And we can go to zero seven five.

UNIDENTIFIED MAN: Zero to...

NORTHAM: The Maersk McKinney Moller shuttles between ports in Asia and Northern Europe, the world's busiest trade route. No U.S. port is able to handle a ship this size. Several European ports improved their facilities, dredging their waterways and upgrading the size of their cranes in order to unload containers from this super wide vessel. And ship's Captain Jes Meinertz says the Chinese are constructing new terminals at an amazing rate.

MEINERTZ: They are just building more and more terminals, bigger and bigger terminals. I mean you have so much more gear available when you come alongside than in some of the European ports.

NORTHAM: It was in 2010 - well into the global recession - that Maersk Lines made the decision to create this new class of megaship. Michael Heimann, senior portfolio manager at Maersk Line, was part of the development team.

MICHAEL HEIMANN: We were actually tasked with having come up with a design which was at least 30 percent more efficient than other big container ships. Already there, we needed to try and think in different ways than what we had seen in ship design before.

(SOUNDBITE OF ENGINES)

NORTHAM: It's here, in the bowels of the ship where the Maersk team broke with tradition. It made changes to the engine size and propellers, and improved ways to capture energy to more efficiently power the vessel. The ship moves two to three knots slower than others, which cuts both CO2 emissions and fuel costs - the ships biggest expense - by at least half. But they also made fundamental changes to the shape of the vessel, in order to get as many containers on board as possible. Its economy of scale, says Heimann.

HEIMANN: Obviously, the more containers that we can put on, the more containers that have to split the cost of the fuel on.

NORTHAM: Richard Meade, with Lloyd's List, a shipping industry news provider, says that's a great argument but only if the ship is fully loaded.

RICHARD MEADE: A ship like the Maersk McKinney Moller is a fantastic advance for the industry, as long as it is full. If it is half empty, it is probably one of the most inefficient ships ever built. And this is the great gamble.

NORTHAM: It's a gamble Maersk is willing to make, based on the belief that global trade will bounce back from the recession. The company ordered 20 of the Triple E vessels from South Korean shipbuilder Daewoo, at $185 million apiece. Other shipping companies have also placed orders for similar sized vessels.

(SOUNDBITE OF WATER)

NORTHAM: Our next stop is Aarhus, Denmark where I depart. After that, the Maersk McKinney Moller has a couple other European stops before heading back to Asia.

Jackie Northam, NPR News.

(SOUNDBITE OF MUSIC)

MONTAGNE: And tomorrow, Jackie is back in the U.S. with a story about how the energy boom here is breathing new life into America's long-struggling shipyards. Transcript provided by NPR, Copyright NPR.